Media and electrical distribution enclosures or boxes that employ a modular construction typically include a series of vertically stacked individual enclosures, stacked elongated wall segments, or sections that slide relative to one another. Some existing modular distribution enclosures have various shortcomings, drawbacks, and disadvantages relative to certain applications. For example, some vertically stacked enclosures be provided with “knock out” openings, that is, removable partially stamped openings, in the surface of the end walls, to allow for routing of wiring, cable, or components from one enclosure to an adjacently stacked enclosure. Such enclosures are limited by the size of the knock out openings. Moreover, the edges of the knock out openings do not allow for a component to be mounted to the back surface across stacked enclosures. Other enclosures, although modular, suffer from being bulky or otherwise inconvenient to assemble or handle. Accordingly, there remains a need for further contributions in this area of technology.